The following relates generally to wireless communication, and more specifically to physical uplink control channel (PUCCH) for low latency downlink communication.
Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division multiple access (OFDMA) systems. A wireless multiple-access communications system may include a number of base stations, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE).
A UE and a base station may communicate using a low latency physical layer (PHY) configuration, which may include using transmission time intervals (TTIs) that have a shorter duration relative to other TTIs used in the system. These low latency communications may be more sensitive to channel conditions than communications using longer duration TTIs. Thus, some low latency messages, such as control channel messages including acknowledgment information, may be lost, which may result in delays and disruptions in communication between the UE and base station.